Apparatus for assembling an electrode cage for electron discharge devices



Dec. 22, 1959 WQLKE ET AL 2,917,812

ASSEMBLING AN ELECTRODE CAGE FOR ELECTRON DISCHARGE DEVICES OriginalFiled May 26, 1951 APPARATUS FOR 2 Sheets-Sheet '1 K WOLKE ET AL2,917,812

FOR

R. APPARATUS FOR ASSEM L NG ELECTR CAGE SCH E DEVIG Dec. 22, 1959 wELECTRON Original Filed May 26, 1951 2 Sheets-Sheet 2 2,917,812 PatentedDec. 22, 1959 APPARATUS FOR ASSEMBLING AN ELECTRODE CAGE FOR ELECTRONDISCHARGE DEVICES Roy Karel Wollie, Mapiewood, John Anthony Chase,Nutiey, and Frank 5. Piias, Lyndhurst, N.J., assignors to RadioCorporation of America, a corporation of Delaware Original applicationMay 26, 1951, Serial No. 228,386, now Patent No. 2,778,968, datedJanuary 22, 1957. Divided and this application April 26, 1956, SerialNo. 580,952

1 Claim. (Cl. 2925.19)

The present invention relates to apparatus for and a method ofassembling the components of an electrode cage.

This is a division of application of F. J. Pilas, R. K. Wolke, and J. A.Chase, Serial No. 228,386, filed May 26, 1951, now Patent No. 2,778,968,issued Jan. 22, 1957, and assigned to the same assignee as the presentapplication.

Conventional electrode cage assemblies for electron tubes include acathode and one or more other electrodes mounted between a pair ofinsulating spacer members or plates. A serious problem has heretoforecharacterized such cage assemblies.

This problem involves the mounting of the electrodes on the spacerplates. The mounting of the electrodes on the spacer plates usuallyinvolves extending end portions of the electrodes thru suitableapertures provided in the plates. While it is desirable to have as closea spacing as possible between the electrode end portions and the wallsof the apertures in the spacer plates for good support, such closespacing introduces difficulties in extending the electrode end portionsinto the apertures, particularly when the end portions referred to arerelatively fragile and the material of the spacer plate is not flexibleand therefore likely to disintegrate in response to a forced entry.

Accordingly, it is an important object of the invention to provide animproved jig and method for facilitating the mounting of an electrode onan insulating spacer plate.

A further object is to provide an improved jig for mounting parts toform an electrode cage with reduced damage to said parts.

Briefly considered, there is provided according to the invention a noveljig and method which contribute to an improved electron tube cage. 7

The jig and method of the invention are particularly advantageous inconnection with assembling parts to form an electrode cage, where one ofthe parts comprises a spacer plate having apertures for receiving endportions of electrodes and a plurality of slots communicating with eachaperture and forming flexible segments therearound.

According to one aspect of the invention, the flexible segments referredto when engaged by an electrode entering an aperture, are deflected inthe direction of electrode travel to form a funnel for aiding theentrance of the electrode into the aperture with reduced harm to boththe spacer plate and the electrode.

According to another aspect of the invention, a novel jig is providedhaving fingers disposed in a closed array and adapted to enter the slotsreferred to and to supplement the function of the segments in definingedges of an aperture. The fin gers are tapered toward their free endsinwardly of the closed array referred to, so that they form an effectivefunnel for directing an electrode end portion into the aperturementioned, l

Further objects and advantages of the invention will become manifest asthe present description proceeds.

Referring now to the drawing for a better understanding of theinvention,

Figure 1 shows an exploded elevation of parts included in the electrodecage of one type of electron discharge device;

Figure 2 is a side view of an electrode cage assembled from the partsshown in Figure 1;

Figure 3 is a plan view of an insulating spacer plate that may be usedin the cage shown in Figure 2;

Figure 4 is a sectional elevation of a jig that may be used according toone aspect of the invention in mounting the parts shown in Figure 1 toform a cage;

Figure 5 is a sectional elevation of a jig according to another aspectof the invention that may be used advantageously in forming a cage fromthe parts shown in Fig. 1;

Figure 6 is an enlarged partly sectional view along the line 6-6 ofFigure 5 and shows one group of funnelling fingers of the jig inrelation to the structure of a spacer plate and electrode;

Figure 7 is an enlarged partly sectioned view along the line 77 ofFigure 5 and shows another group of funnelling fingers of the jig; and

Figure 8 is a plan view of an electrode cage including a cathode, a gridand an anode assembled by the use of the novel jig and method of theinvention.

Referring now to the drawing in more detail, there is shown in Figure 1thereof, components of one type of electrode cage in connection withwhich the jig and method of the invention find particular utility. Theparts referred to comprise a cathode sleeve 10, an anode 11 having sidewings 12, 13 defining passageways for receiving anode support rods 14,15. The cathode sleeve and anode referred to are supported betweenspacer plates 16, 17 which have apertures for receiving end portions ofthe cathode sleeve and the anode support rods. The electrode cage formedof these parts is shown in Figure 2 and is adapted to be used in a diodetype of electron tube.

One or both of the spacer plates 16, 17, which may be made of aninsulating material such as mica, are provided with tongues or segmentsdefining slots and electrode-re ceiving' apertures or passageways asshown in Figure 3. The aperture 18 is adapted to receive cathode sleeve10 and the apertures 19, 20 are adapted to receive the anode supportrods 14, 15.

The aperture 18 is defined by segments 21, 22, 23, 24. The segmentsreferred to also define slots 25, 26, 27, 28. The segments constitutetongues integral with the spacer plate and flexible by bending alongstraight lines indicated by dotted lines, in response to the forceexerted on the tongues by a cathode sleeve entering the aperture 18.

Each of the apertures 19, 20 for receiving anode support rods 14, 15 isdefined by segments 29, 30, 31, 32. Slots 3.3, :34, 35, 36 communicatingwith the apertures 19, 28 are also defined by the segments referred to.The segments mentioned are integral with the spacer plate and areflexible along straight lines shown by dotted lines in response to thethrust thereon of anode support rods 14, 15, when the same are extendedinto apertures 19, 20.

According to one aspect of the method of the invention, the flexure ofthe segments or tongues defining the apertures 18, 19 and 20, causesthem to assume a position in which they form a partial funnel. Thispartial funnel not only guides electrode end portions into the aperturesreferred to but also serves to widen the aper tures.

For mounting the electrodes referred to on a spacer plate according tothe presently discussed method aspect of the invention, use may be madeof a novel mounting jig 37' shown in Figure 4. The upper surface of the3 jig is provided with cavities S8, 39, 40 defined by edges adapted tobe disposed in substantial registry with the dotted lines along whichthe segments or tongues defining the apertures'18,'19, 20 flex, as shownin Figure 3. The jig includes two locating lugs, one of which is shownat 41 in Figure 4, for engaging apertures 42, 43 shown in Figure 3 toproperly register the dotted line portions of the piate with the edgesof cavities 38, 39, 40. The bottoms 44, 45, 46 of the cavities referredto serve as stops for the electrode end portions to be extended into theapertures 18, 19, 20. The bottoms of cavities 38 and 49 are lower thanthe bottom of cavity 39 to permit adjacent ends of the anode supportrods 14, 15 to extend farther from the plate 16 than the adjacent end ofthe catho'de sleeve 10. The jig is also provided with a mandrel 47 onwhich the cathode sleeve is adapted to be threaded for registry with theaperture 18 in the spacer plate. The bottom 45 of cavity 39 may beraised or lowered by movement of shaft 48, the upper surface of whichforms the cavity bottom 45. The shaft 48 may be locked in desiredposition by lock screw 49.

As shown in Figure 4, when the anode support rods 14, and the cathodesleeve 10 is urged into apertures 18, 19, of the spacer plate 16, thesegments defining the apertures flex to form a funnel-like structure. Ifany of the electrodes is improperly registered with any of theappropriate apertures referred to, it is urged into such registry by thesloping surfaces of the segments forming the funnel-like structure. Thisfacilitates a mounting operation and renders automatic mountingprocedures practicable. It also makes feasible a continuing engagementbetween the electrodes and the spacer plate resulting from a forceexerted by the flexed segments on the electrodes. This last mentionedadvantage requires that the apertures 18, 19, 20 in the spacer plate beslightly smaller than a cross-section of the electrode portions receivedtherein.

According to another aspect of the invention a mounting operation isprovided during which the segments defining the apertures 18, 19, 20therein are not flexed. A novel jig 50 for use in this type of operationis shown in Figure 5. This jig is similar in some respects to jig 37shown in Figure 4. For example, it has cavities 51, 52, 53 in its uppersurface, the cavities having bottoms 54, 55, 56 serving as stops forelectrodes to be mounted. The bottom 55 is formed by the upper endsurface of cathode.

an adjustable shaft 57 and the shaft referred to is fixed afteradjustment by lock screw 58.

However, jig differs from jig 37, in that the cavities 51, 52, 53therein have transverse dimensions substantially equal to thecross-sections of end portions of electrodes to be received therein. Theedges of the cavities are not therefore in registry with the dottedlines shown on the spacer plate in Figure 3.

To facilitate extension of the electrodes into the apertures 18, 19, 20in the spacer plate, without flexing the segments thereof, the jig 56 isprovided with a plurality of fingers or risers 59, 60, 61, 62 aroundcavity 52 as shown in Figure 6, having bevelled sides 63, 64, 65, 66 forforming a funneHike structure for guiding cathode sleeve 10 intoaperture 18 in the spacer plate. Around each of the cavities 54, 56 arealso disposed a plural ty of risers 6'7, 68, 69, 70 as shown in Figure7, having bevelled sides 71, 72, 73, 74 forming funnel-like structuresfor guiding the anode side rods 14, 15 into apertures 19, 20 in thespacer plate.

The slots in the spacer plate render the advantageous jig shown inFigure 5 feasible. The slots 25, 26, 27 and 28 in the spacer platepermit extension of the risers in the jig through the plate, to providethe funnel-like structure referred to for guiding the cathode sleeve 10into aperture 18. The slots 33, 34, 35, 36 adjacent each of theapertures 19, 20 in like manner permit extension through the plate ofrisers 67, 68, 69, 70 for guiding the anodes side rods 14, 15 intoapertures 19, 20.

Each of the mounting modes shown in Figures 4 and 5 has distinctadvantages. For example, when the spacer plate is made of flexiblematerial such as mica, the mounting procedure shown in Figure 4 hasparticular advantages in that it both provides a guide for theelectrodes into the spacer apertures, and also assures a subsequent firmengagement between the spacer plate and the electrodes. However, wherethe spacer plate is made of a material such as ceramic that is incapableof flexure without breaking, the novel and advantageous jig of Figure 5is of particular usefulness for guiding the electrodes into theapertures in the spacer plate.

It will be observed that while the slots 26, 28 are utilized in themounting procedure shown in Figure 5, the slots 75, 76 are necessary fordisposing the risers 59, 61 adjacent the path followed by a cathodesleeve during a mounting operation. If leakage slots 26, 28 wereisolated from cathode aperture 18, as in the prior art, the advantageousoperation permitted by jig 50 could not be carried out. I While theforegoing description has'concerned spacer plate 16, it will beunderstood that spacer plate 17 shown in Figure 2 may be of similarconstruction. Thus, the mounting procedures shown in Figures 4 and 5 maybe employed for first mounting the electrodes on one plate, and thenmounting them on the second plate.

It will be noted that the segments 21, 22, 23, 24 shown in Figure 3, areformed so that each segment has one set of opposite and parallel edges.This results in a segment having increased flexibility. While Patent1,967,208 to Krahl shows a spacer plate having a cathode aperturedefined by two segments, the edges of the segments extend in angulardfrections thus reducing the flexibility of thesegments. Krahl showsonly two segments for engaging his cathode sleeve while the spacer plateof the present invention has four segments for supporting a Therefore, agreater burden of support is assigned to each of the segments of Krahlthus making mandatory an increased rigidness of the segments. Thisdegree of rigidness is not necessary in the case of the segments of thespacer plate of the invention, because the support of the cathode sleeveis distributed among four segments.

It will be apparent, therefore, that a novel jig and method are providedfor facilitating the assembling of parts toform an electrode cage.

What is claimed is:

A jig for facilitating the mounting of an electrode on an insulatingspacer plate, said jig having a planar surface for receiving said plate,a cavity in said surface adapted to be placed in registry with anaperture in said plate, and a plurality of fingers rising'from saidsurface and disposed around said cavity and adapted to be rece'ved inslots in said spacer plate, said fingers including a side portionadjacent said surface in registry with spaced edge portions of saidcavity, and a bevelled side portion remote from said surface for forminga funnel for guiding an electrode into said aperture in the spacerplate.

, References Cited in the file of this patent UNITED STATES PATENTS

